Add 2 cups of whole grain spelt to a half gallon jar. Pour in enough water to fill 3/4 of the half gallon.
Add 1 or 2 tablespoons of apple cider vinegar.
Shake to mix and let set for 12 to 24 hours. The longer you let it sit, the more digestible the grain becomes.
The grain will swell up to fill the jar.
Store in your refrigerator, and pull out as much as you need when you need it.